4-07: Little Green Men
Quark, Rom, and Nog accidentally transport themselves back to the Roswell Incident on Earth in 1947.
4-03: The Visitor
When a freak accident traps Sisko in a time paradox, only re-appearing every few years, Jake spends the remainder of his life trying to save him.
4-02: The Way of the Warrior, Part II
DS9 is center ground as the Klingon conflict intensifies. Gowron tries to persuade Worf and the Defiant rescues a Cardassian convey carrying Gul Dukat.